I've driven about everything and i have to say a new model Volvo has the best ride in my opinion.They might not be the shinny large cars that alot prefer but they do ride good.
Out of the choices you've given, Volvo 770. This does not mean it is the best. It merely means that it rides the best out of all of the limited choices you've provided.
And kid, let me tell you that it was not much of a selection; The FLD and classic are identical except for the set back axle----both of them ride sucky.